Press with fluid-conducting strain rod



Oct. 8, 17940. A, MULLER 7 2,217,025

PRESS WITH FLUID-CONDUCTING STRAIN ROD Filed Nov. 26, 19:5 4 Sheets-Sheet 1- JOHHN H.MULL E 8 Oct. 8, I940. JQA. MULLER 2,217,025

PRESS. WITH FLUID-CONDUCTING STRAIN ROD Filed Nov. 26, 193 4 Sheets-Sheet 2 flg' .2 37

45' v 50 48 42 I 5; 2 ,?1- 24 54 6 5 I 47 44 Jmm J OHAN H- 'M ULLER' 4 Shoets-Shetfi Jmam HANA-MULLER,

J. A. MULLER Filed Nov. 26, 1931 PRESS WITH FLUID-CONDUCTING STRAIN ROD 6 m 3 h u Q m a. ,u 4 n 3 m Oct. 8, 1940.

Oct. 8, 1940.

J. A MULLER PRESS "WITH FLUID-CONDUCTING STRAI ROD Filed Nov. 26, 1 37- 4 Sheets-Sheet 4 m N N Mf /WW a Q J-0mm Amt/1. LER, N v

Patented Oct. 8, 1940 Johan A. Muller, Mansfield, Ohio, assignor to The Hydraulic Press Com, Inc., Wilmingto 'a corporation of Delaware Application November 2c, 1931, Serial No. 176,503 9 Claims. (01. 100-71) This invention relates to. hydraulic machinery, and in particular to hydraulic presses.

One object of this invention is to provide a hydraulic press, wherein at least one of the strain rods interconnecting the top and bottom .members of the press is hollow for the purpose of conducting fluid. a

Another object is to provide a hydraulic press having hollow strain rods for conducting fluid from the pump to hydraulic devices mounted at a remote portion of the press, thereby eliminating the necessity of rimning pipes to that portion of the press.

Another object is to provide a hydraulic presshaving top, and bottom members interconnected by strain rods, at least one of which is hollow for the purpose of conducting fluid, thereby eliminating the pipes ordinarily required for this purpose, and simplifying the construction of the machine.

In the drawings:

Figure l is a front elevation of one embodiment of the press of this invention.

Figure 2 is a side elevation of the press shown in Figure 1.-

Figure 3 is a vertical section along the line H in Figure 4.

Figure 4 is a horizontal section along the line H in Figure 2.

Figure 5' is an axial section through one of the push-back cylinders of the press.

In general, the press of this invention consists of top and bottom members, interconnected by strain rods. At least one of these strain rods is hollow and is provided with fluid connections whereby the hollow strain rod serves as a fluid-conducting conduit for conducting fluid to and from hydraulic devices located in a.

remote portion of the press. In particular, the hollow strain rods may be used to conduct fluid from a pump mounted on the top member of the press to the push-back cylinders, hydraulic cushions, or other hydraulic devices mounted in the bottom member of the press.. Fluid connections made between such devices and the hollow strain rod avoid the necessity i'or the use of the piping ordinarily required in such presses, simplify the construction of the press, improve the a pearance and strengthen the hydraulic circui The hollow strain rods being of considerably greater strength than ordinary pipes, are substantially without the possibility of leakage or breakage.

Referring to the drawings in detail, Figures 1 and 2 show one embodiment of a press em- -tively. 'Ihe'upper caps II are provided with ploying the fluid-conducting hollow strain rods according to this invention. This press consists of a top member II and a bottom member ll, interconnected by strain rods II, II, I4 and 5 It (Figure 4). It isimmaterial which or how many of the strain rods are hollow as the choice will depend upon the particular installation.

- For purposes of illustration, however, in the present embodiment the press is shown as hav- 1o ing two rearwardly disposed strain rods l4 and It provided with bores I8 and H for fluid-conduction purposes. The upper ends of the strain rods I! to It are threaded, as at I8, and the lower portions thereof threaded, as at II, for 15 the reception of nuts 21!.

Secured to the upper and lower ends of the bores l6 and II in the strainrods I4 and I! are the fluid connection caps 2i and 2!, respecfluid "passages 23 interconnected by-the conduit 24, whereas the lower caps 22 are provided with fluid passages 25, not interconnected but leading by way of pipes 26 (Figure 2) to the ports 21 (Figure 5) in the lower ends of the push-back cylinders II. The push-back cylinders 28 are mounted upon the press bottom member or base II, and are supported thereon by flanged portions 29.

Reciprocating within the push-backcyli'nders 28 are the push-back plungers 3!, the upper ends 30 of the push-back cylinders 2! being closed by the glands II encircling the push-hack'plungers 30. The upper ends of the push-back plimgers 30 are secured to the press platen 32 (Figure 2).

' The latter moves downwardly under the influence 35 of the .main plunger 33 secured thereto. and reciprocating in the main cylinder bore ll of the main cylinder 35 mounted in the press top member It. A gland 3t, threaded into thespace surrounding the main plunger 33, prevents leak- 40 age from the main cylinder bore 34. surmounting the main cylinder 35 is a surge tank" for the purpose of supplying fluid to the various hydraulic devices. The platen 32 is provided with plates 38 bolted thereto, as at 3!, and re- 45 ciprocating in the guideways 4| (Figure 1) provided in the press side members 4|. The latter are arranged between the top and base members i0 and II and extend around the strain rods H to it, previously described.

Pressure fluid for operating the press is provided by a reversible variable delivery pump 42. operated by an electric motor 43 (Figure 1). Any suitable form of pump may be used. the reversible variable delivery type shown being merely for leading purposes of illustration and not by way of limitation. The pump '42 is provided with a forward 7 cylinder 35. From the return connection tank connection I. From the T-connection the line Ii leads to the right-hand fluid connection cap 2i, which is connected to the lefthandcap 2| by means of the pipe 24, previously described.

The pmnp s: is provided with a safety centering device I2 on one side and a servomotor unit it on the omollte side. These details of pump construction form no part of the present invention, and a disclosure thereof-will be found in the copending application Ser. Dim-170,250, filed October 21, 1937, of Walter Ernst. This appli-, cation has become Patent No.

operative to move the shirt ring or flow-control member of tin: reversible variable delivery pump 42, this pump being oi'the radial pistontype wherein the delivery is regulated by varying the eecentridty of the rotor or piston actuator relatively to the primary rotor or cylinder barreLinamanner-knowntothoseskilledinthe hydraulic numpart.

The operation or the servomotor unit 53 is controlled by a servomotor control valve rod 54, connected to a lever 55 pivotally mounted upon a pivoted link 56. The opposite end of the lever II is pivotally connected to a link-51 leading to a rocking lever 58 pivotally mounted, as at 59, upon the porting bracket 60 (Figure 2) which in turn, is mounted upon the press top Pivotally connected to the lower end oftherockingleverilisalinklLwhichisin turn, to an arm 62 mounted upon the pivot shaft 63 and serving to rock the lever 64. To one end of the lever it the armature 65 of a solenoid 0G is ivotally connected, whereas the opposite end terminates in a'yoke i1 engaging a collar '8 upon the press control rod 69, which gear casing Ii and operated by the hand wheel control rod 6! and shift the pump 42 to its neutral delivery position at the top of the return stroke of the main platen 32. The limit switch I2 is connected in circuit with the solenoid 66, the latter likewise serving to shift the servomotor control valvemd 54 through the various links and levers arranged therebetween.

the line l8 leads to the surge becoming a suction connection.

2,184,665, issued I .December 26, 1939. The servomotor unit 53 is Fluid i8 0 return connection The pressure: which the platen l2 exerts is regulated by the tonnage control device ll, operated by the hand wheel II and connected by the line 80 to one 01' the push-back cylinders 28.

press is also provided with an emergency stop 8| (Figure 2) serving to engage the platen 32 in the rod 54 to cause it to deliver pressure fluid through The event that the other control features accidentally the connection 44, the connection I! temporarily Under these conditions, pressure fluid flows from the pump l2, along the line 46 to the main cylinder connection 41, where it enters the main cylinder II and causes the main. plunger 22 and platen 22 to move downwardly.

Meanwhile, the suction connection ,45 takes in pressure fluid along the line 48 Iron the surge tank 2! by way of the surgetank"connection withdrawn from the push-back cylinders 28 by way of the ports 21, the pipes 26, the lower connection caps 22, the strain rod bores l0 and-ll, the upper connection caps 2|, the pipe 24 and passages 23 and the pipe II connected to the pipe 48 leading to the suction connection or downwardly until its electrohydraulic control system operates to actuate the solenoid It, as by operating a pressure-responsive switch (not shown).

45. The platen proceeds When this occurs the servomotor control valve rod 54 of the servomotor it is shifted through the links and levers connecting it with the sole noid armature 65, thereby causing the forward connection It and return connection 45 to become respectively the suction and pressure connections. Fluid is now wl hdrawn from the main through the line 48 ing through the top bores l6 and I! in and I5.

The pressure fluid flows these hollow strain the pipes s: and 24 lead connection caps 2|, to the the hollow strain rods l4 downwardly through rods II and I5, thence through the lower connection caps 22 and pipes 26, to the push-back cylinders 28.

Under the influence of this pressure fluid the push-back plungers 30 rise, lifting the main platen 32 until the platen arm 15 and nut 14 raise the press control rod 69 to shift the servomotor A valve rod 54 to a position wherein the shift ring or flow-control member 01' the reversible variable delivery pump 42 will be placed in its neutral or zero delivery position. The platen 32 is then held in its raised or return position until the operator presses the push-button switches at the push-button controlv station 82 to cause the press to execute another pressing stroke. If the electrohydraulic press control system, however, is set for full automatic rather than semiautomatic operation, the platen 32 on reaching the top of its return stroke immediately executes another pressing stroke, and continues to do so until halted by the operator, in a manner dependcontrol Patent is:

trol system. The particular electrohydraulic control system employed in the press forms no part of the present invention.

According to the present invention, therefore, the hollow strain rods I4 and I5 serve to conduct fluid between remotely situated portions of the press, and thereby eliminate the pipes formerly required for this purpose. The simplification and strengthening of the press resulting from this invention efiect an improved dependability and freedom from breakdowns which arose in previous presses by reason of leakage in such pipes. It will also be seen that hydraulic devices other than push-back cylinders may be operated by pressure fluid received through the hollow strain rods. For example, one of the .dies maybe mounted upon a hydraulic cushion, receiving pressure fluid through a hollow strain'rod. Alternatively, the construction of this invention may be employed in a hydraulic metal drawing press wherein one of the plungers, such as the clamping plunger, may be operated by pressure fluid received through a hollow strain rod. It will be understood that I desire to comprehend within my invention such modifications as come within the scope of the claims and the invention.

Having thus fully described my invention, what I claim as new and desire to secure by Letters 1. In a hydraulic press, a top member, a base member, strain rods interconnecting said members, at least one of said strain rods having a fluid-conducting passageway therein, a cylinder, a plunger therein, a'source of pressure fluid, and

a hydraulic circuit connecting said source with said fluid-conducting passageway near one end of said strain rod, said cylinder being connected to said strainrod passageway near the other. end of said strain rod,

2. In a hydraulic press, a top member, a base member, strain rods interconnecting said members, at least one of said strain rods having a fluid-conducting pasageway therein, a cylinder,

end-members, at least one offsaid strain rods having a fluid-conducting passageway therein, a

cylinder, a plunger therein, a source of pressure fluid,' a hydraulic circuit connecting said source with said cylinder and with said strain rod passageway near one end of said strain rod, and a hydraulically-operated device connected to the fluid-conductingpassageway neanthe other end of said strain rod.

4. In a hydraulic press, oppositely disposed end, members, strain rods interconnecting said end members, at least one oil-said strain rods havinga fluid-conducting passageway therein, a cylinder and plunger associatedwith .one or said end members and connected to said fluid-conductiing passageway near one end of said strain rod, a source of pressure fluid. and a hydraulic circuit connecting said source with said strain rod'passageway near the other end of said strain rod.

5. In -a hydraulicv press, oppositely disposed end members, strain rods interconnecting said end members, at least one of said strain rods having a fluid-conducting passageway therein, a cylinder and plunger associated with one of said end members, a source of pressure fluid; a hydraulic circuit connecting said source with said cylinder and connected to said strain rod passageway near one end of said strain rod, and a hydraulic motor connected to said fluid-conducting passageway near the other end' of said strain rod for receiving pressure-fluid therethrough.

6. In a hydraulic press, oppositely disposed end members, strain rods interconnecting said end members, at least one of said strain rods having a fluid-conducting passageway therein, a main cylinder, a main plunger therein, a source of pressure fluid, a hydraulic circuit connecting said source with said main cylinder, and with said fluid-conducting passageway near one end of said strain rod, a platen; connected to said main plunger, a push-back cylinder, a push-back plunger therein connected to said platen, and means hydraulically connecting said push-back cylinder with said fluid-conducting passageway near the other end or said fluid-conducting strain rod.

7. In a hydraulic press, upper and lower end members, strain rods interconnecting said end members, at least one of said strain rods having a fluid-conducting passageway therein, a main cylinder and main plunger associated with one of said end members, a push-back cylinder and push-back plunger associated with the other of said end members, and connected to said fluidconducting passageway near one end 0'! said strain rod, a pump, and a hydraulic circuit connecting said pump with said cylinders and with said fluid-conducting passageway near the other end of said fluid-conducting strain rod.

8. In a hydraulic press, oppositely disposed end members, strain rods interconnecting said end members, at least one of said strain rods having a fluid-conducting passageway therein, a cylinder with a plunger therein mounted on one end member, a pump mounted on the other end member, fluid connection terminals secured to said 7 ends thereof, and a hydraulic circuit connecting said pump with said cylinder by way of said strain rod passageway and said fluid connection terminals' 1 9. In a hydraulic press, upper and lower end members, strain rods interconnecting said end conducting passageways therein, a main cylinder and main plunger connected to one of said end members, a pair of push-back cylinders and pushback plungers, connected to theother. of said end members, a platen connected to said plungers, a pump, and a hydrauliccircuit connecting said .fluid-conducting strain rod near the opposite -members, two '01" said strain rods having fluidpump with said cylinders by way of, said fluidconducting strain rods.

, JOHA N A. MULLER. 

